1. Field of the Invention
The present invention relates to a light source device with a light guide plate arranged as a parallax barrier to enable stereoscopic vision, and a stereoscopic display apparatus using the light source device.
2. Description of Related Art
In the past, a parallax-barrier stereoscopic display apparatus has been known as one of stereoscopic display methods enabling stereoscopic vision with a naked eye without need of special eyeglasses. FIG. 14 shows a typical configuration example of a parallax-barrier stereoscopic display apparatus. In the stereoscopic display apparatus, a parallax barrier 101 is disposed facing a front face of a two-dimensional display panel 102. In a typical structure of the parallax barrier 101, shading portions 111 shading display image light from the two-dimensional display panel 102 and stripe openings (slit portions) 112 transmitting the display image light are alternately provided in a horizontal direction.
The two-dimensional display panel 102 displays images based on three-dimensional image data. For example, a plurality of parallax images different in parallax information from one another is prepared as three-dimensional image data, and, for example, a plurality of stripe-shaped, divided images extending in a vertical direction is cut out from each parallax image. The divided images are alternately arranged in a horizontal direction for the parallax images, and therefore a composite image, including a plurality of stripe-shaped parallax images in a screen, is formed, and displayed on the two-dimensional display panel 102. In the case of the parallax barrier type, the composite image displayed on the two-dimensional display panel 102 is viewed though the parallax barrier 101. Width of each divided image to be displayed or slit width of the parallax barrier 101 are appropriately set, and therefore when a viewer watches a stereoscopic display apparatus from a predetermined position or in a predetermined direction, light of different parallax images may be separately injected into left and right eyes 10L and 10R of the viewer through the slit portions 112. In this way, when a viewer watches a stereoscopic display apparatus from a predetermined position or in a predetermined direction, the viewer senses a stereoscopic image. To achieve stereoscopic vision, different parallax images need to be shown to the left eye 10L and the right eye 10R. Therefore, at least two parallax images, an image for right eye and an image for left eye, are desired. When at least three parallax images are used, multi view may be achieved. An increased number of parallax images enable stereoscopic vision in correspondence to change in position of a viewing point of a viewer. In other words, motion parallax is achieved.
The parallax barrier 101 is disposed in the front of the two-dimensional display panel 102 in the configuration example of FIG. 14. However, for example, when a transmissive liquid-crystal display panel is used, the parallax barrier 101 may be disposed in the back of the two-dimensional display panel 102 (see FIG. 10 of Japanese Patent Publication No. 3565391 and FIG. 3 of Japanese Unexamined Patent Application Publication No. 2007-187823). In this case, the parallax barrier 101 is disposed between the transmissive liquid-crystal display panel and a backlight, and therefore stereoscopic display may be achieved in accordance with the same principle as in the configuration example of FIG. 14.